#include <stdio.h>
#include <math.h>
#include <errno.h>

int main()
{
    printf("%f\n", INFINITY);
    printf("%f\n", NAN);
    printf("%d\n", math_errhandling); // 2 : Exceptions raised by math functions.
    double r = sqrt(-1);
    printf("%f\n", r); // nan
    printf("%d\n", errno);
    return 0;
}